1. Field of the Invention
The present invention relates to a lens fixing mechanism and an image capturing device thereof, and more specifically, to a lens fixing mechanism utilizing a protruding structure of a lens clamp to pass through a breach structure of a lens base for clamping a lens module and an image capturing device thereof.
2. Description of the Prior Art
In general, a conventional image capturing device (e.g. a monitoring camera) utilizes a lens module to focus received images on an image sensor (e.g. CCD (Charge Couple Device), CMOS (Complementary Metal Oxide Semiconductor sensor)) for image capturing. Thus, when the lens module is deflected, the image capturing quality of the image capturing device is influenced greatly so as to cause local image blur. Assembly misalignment or loosening between the lens module and a lens base for fixing the lens module is the main reason of the aforesaid deflection of the lens module.
In practical application, a conventional method for fixing the lens module to the lens base involves locking screws into the lens base for clamping the lens module after the lens module is disposed through the lens base, so as to prevent the lens module and the lens base from loosening when the lens module and the lens base receive external impact. Furthermore, in another conventional fixing method, the lens module could have damping oil coated thereon and could be screwed into the lens base for filling the thread gap between the lens module and the lens base with the damping oil, so as to prevent the lens module and the lens base from loosening.
The aforesaid methods usually cause deflection of the lens module due to the uneven screwing force and uneven coating of the damping oil. Furthermore, the fixing method for utilizing the screws to clamp the lens module could also cause damage of the lens module due to the excessive screwing force. The aforesaid problems could be solved by utilizing a C-shaped clamp to pack the lens base for causing inward deformation of the lens base. Accordingly, the lens module could be clamped tightly by the C-shaped clamp and the inwardly-deformed lens base. However, this fixing method not only causes elliptical deformation of the C-shaped clamp so that one-sided deflection of the lens module may occur, but also causes the problem that the C-shaped clamp is unable to deform the lens base if the lens base is made of material with high hardness (e.g. metal).